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AI Controlled helicopters collide with terrain and buildings while loading and unloading troops
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  1. While performing loading and unloading, AI controlled MH-9s do not land, only hover 1 meter above ground and do not stay in place, sometimes flying around until the passengers get in or out. During this drunk maneuvering they tend to hit everything around.
  1. Sometimes they get over slope and drop passengers there, killing them.
  1. Prior to landing or during take off they do not avoid obstacles, so sometimes they hit a tree in restricted landing zones or they land uphill or downhill and subsequently crash.
  1. Even if you can unload them without helo crashing, when you call them for extraction from the same place, they wait for couple minutes over the required LZ and then land couple hundred meters away.
  1. If you are a player in the group to load, the troops do not load and unload automatically but you always have to order them to do so (if you load or unload before them, the helicopter does not wait for the rest of the unit to load and unload and flies away). {F18456} {F18457} {F18458}


Legacy ID
AI Control / Commanding
Steps To Reproduce

Create waypoint with hidden LZ for unloading and subsequent loading (transport unload + get out and load + get in synchronized) of troops onboard ("moveincargo") in a restricted LZ (some obstacles around).

Event Timeline

matkob edited Steps To Reproduce. (Show Details)Mar 26 2013, 1:33 PM
matkob edited Additional Information. (Show Details)
matkob set Category to AI Control / Commanding.
matkob set Reproducibility to Sometimes.
matkob set Severity to Major.
matkob set Resolution to Fixed.
matkob set Legacy ID to 1024461907.May 7 2016, 1:09 PM
Bohemia added a subscriber: oukej.Mar 26 2013, 1:33 PM
matkob added a subscriber: matkob.May 7 2016, 1:09 PM
matkob added a comment.Apr 3 2013, 8:21 PM

The more patches the worse the heli AI. I created a mission in the editor with 7 helos(3 little birds, 2 Ka-60 empty with pilots vie get in and 2 AHs). Normally during the insertion at least 1 of the little birds crashes. Immediately after the insertion maybe 1 or 2 more - mostly little birds (AI controlled empty Ka-60s do a bit better but not always). During pick up usually 1 or 2 as well. And during maneuvering also 1 or both AHs while supressing enemy hit the hills. So it is a great success if at least 3 or 4 helos come back. I think this is a serious thing which needs improvement.

oukej added a comment.Apr 4 2013, 9:03 AM

Thank you for the feedback!
Please could you provide your mission? If possible cut it to be as simple as possible while retaining high probability (ideally 100%;) of AI crashing.

I uploaded the mission file. Best way is to play it as a civilian observer in the village(for now it is the basic preset - for better view either use mccsandbox or go to the higher ground). Radios are Alpha 1 for executing the raid after insertion. Alpha 2 for picking up the raid element. Alpha 3 for picking up the security elements. Alpha 4 for RTB. Alpha 5 and 6 for requesting QRF. Alpha 0 for requesting CAS.
Folloving mods are used:

oukej added a comment.Apr 4 2013, 1:35 PM

Thanks, you've shocked me a bit ;D
Would it be possible, please, to cut it so it's as simple as possible (as little amount of units necessary and a specific problematiz LZ placement) and using only the vanilla Alpha game, withou any community made content?

I was not able to reproduce the crashing using only the steps you described in repro but without cleanly isolating the ill behaviour we can't clearly diag where the bug is hidden.

matkob added a comment.Apr 4 2013, 2:47 PM

Now it should work without any addons. There are no enemies. Radios - alpha1 for movement to extraction (men+helos). alpha2 for extracting assault element. Alpha 3 for extracting security. alpha4 for rtb. alpha0 for calling helo CAS. When I was trying to play this one, first one of the AH flew somewhere else. During the insertion southern security crashed. Then one of little birds on its route to its assembly area. After requesting extraction only one helo was landing at a time using the same heliport (invisible). The helo for extraction of remaining security used different heliport as supposed to. The AHs did not return back on signal.

oukej added a comment.Apr 5 2013, 12:34 PM

I've meant rather one helicopter + one transported unit, nothing else :) As atm I'm afraid I can't investigate your mission design.

I've cleared the mission and tried only how AI can deal with the hidden heliports placed by you.

MH-9 had no problems landing on all the LZs you are using. Even though I'd dare to say some of them are are placed so even irl a pilot would not be happy about being forced to land exactly at such spots :]

matkob added a comment.Apr 5 2013, 2:57 PM

Maybe it is a problem only if you are using several helos at once. All I want is they just fly in, land or hover 1 m AGL (exactly over their designated helipad - not the neighbour's one or in 20 m diameter +-) and do not move until all troops disembark (preferably all together - especially if they are on side rails or the door is big). Sometimes they move around during troops disembarking in 2 m altitude (they sweep in all 4 directions even 20 or 30 m hitting trees and buildings which are fairly apart of the helipads - seems the pilot loses control in hovering). Then they should take off to such altitude that they clear all obstacles and fly away (happened to me that they used to crash even during normal flight after insertion).
Regarding the pick up - they should fly in from designated direction and angle (I was looking everywhere but did not find a script command for a waypoint facing), they should not wait 4 minutes before they start landing one by one (mostly on the same LZ) so instead of extraction lasting 5 or 6 min it should be done in less than 40 seconds for all helicopters. During the extraction they use to hover 2 m AGL - sometimes after loading 2 troops losing balance and sweeping to the side even 20 or 30m - the rest of soldiers chasing them. If there is an obstacle close by - they hit it.


oukej added a comment.Apr 29 2013, 9:37 AM

After some consulting and testing I would dare to say the design is wrong to force too many helicopters that are not in one group (therefore not coordinating their paths) into a small area moreover with some challenging LZs.

In a warzone similar situation might have lead to an accident, a collision as well. Allowing such uncoordinated dense traffic would be rather a HQ-failure. The helicopters indeed do crash into each other or the environment, but only if they are forced to do avoid several another collisions at one moment. That's why irl there's always a human pilot, AI can never beat the human improvisation :) And even though the accidents are still the major cause of death and injuries in today's warzones.

About the directions and pinpoint desing. Generally said it is best to leave the AI some freedom. Especially extensive scripting and making the AI to perform a simple action in an precisely delineated way can have a much worse result than giving the AI sort of military-fashioned, simple orders, and leave it to chose its own way to deal with it. In my opinion a mission designer in ARMA is rather a commander (with all the risks such person has to keep in mind) than a movie director.

I'm sorry for atm I can't assist you with the mission design itself, please don't hesitate to use our forums in that regard.

To be able to investigate wrong AI behaviour, I need a very simple repro, e.g. 3 AIs max.

Ja dekuju :)

oukej added a comment.Apr 29 2013, 9:40 AM

Summary edit: one issue/one report

If I place 2 helos and group them, the second does not even spawn at the startup. I sorted this out by using waypoints (join, join and lead). Yes, the zones are restricted (US manuals say 25m diameter for MH-6), however the main problem still persists: Once the helicopter lands for insertion, the first person jumps out and the helicopter starts flying around hovering in 30 m diameter while the rest disembark (the same with loading). Regarding giving AI some freedom - I would not insist on precise scripting if the AI would be reliably enough to let the decide =DDDDD. Attaching mission.sqm with 2 helos (first it is necessary to get in the choppa with the team). Radio alpha for departing the assembly area, radio bravo for extract.

matkob added a comment.May 6 2013, 5:58 PM

After latest patches the AI behavior even worse. They dropped my troops from 10 m altitude and the second heli crashed after it unloaded 2nd man.

oukej added a comment.May 23 2013, 6:18 PM

Could you please retest with the latest data? The helicopter AI was slightly improved and should be less prone to crash/fly more carefully.

I had only 1/10 success with a clearly wrong behaviour (Pilot landing on a tree and then safelanding), but nothing reliable.

A note: The desired behaviour is that AI always tries to land at the designated invisible helipad, even if it was placed in the middle of a forest

During infil I had 1 crash. During exfil every time at least 1 helo. During infil they seem to be more stable, even they are swinging a bit (anyway, at least trying to be in one place until everybody disembarks) but during exfil they roll over on the terrain. Still need a bit more stability. Can we also add combat infil - that means they four on rails exit almost at once and the 2 inside after? Este to otestujem tento tyzden.

The behaviour is a bit better now but sometimes during pick up the helos fly and individuals are chasing them around until it crashes, especially in an uneven terrain.

Since last couple patches it went terrible again. From 6 transport helicopters none came from the mission. (2 hawks 4 birds). Couple days ago all of them returned from the same mission. They stopped following waypoints, helicopters in formation do not keep it and they are flying around even with command "allowfleeing 0".

matkob added a comment.May 3 2014, 9:26 PM

The problem still persists, the helicopters do not stop in place while troops are unloading but are floating around in low altitude, like 1 m, hitting troops on the way and hitting structures.

Improved: AI helicopter landing

The AI should now be significantly better at landing a helo and also at pickup up the right, safe LZ.

Could you please re-check and ev. confirm?

Thanks a lot!

Mass-closing all resolved issues not updated in the last month.

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